[Dynamic characteristics of compensatory tracking behavior in adults with cerebral palsy]

Dynamic characteristics of motor control system of adults with cerebral palsy was examined by a compensatory tracking task with step wave, sine wave and random wave targets. The velocity of responses to step wave targets by the cerebral palsy subjects was lower than that by the normal subjects. In terms of the closed-loop transfer functions in responses to sine wave targets compared with those to random wave targets, it was revealed that the normal subjects could switch their feedback tracking behavior to precognitive control behavior in order to reduce their tracking phase lag which was greater with random wave targets than with sine wave targets, while the cerebral palsy subjects could not do so. These results suggest that the cerebral palsy subjects have difficulty in generating precognitive control behavior to match sine wave targets.